Support Unicode art (as well as ASCII art).

[Trent W. Buck]

I have historically used Unicode box drawing characters in my source
document, both for compactness and expressiveness. It seems that
aafigure's support for such codepoints could be significantly improved.

Below is an example of a Unicode art network diagram.

I've found in the past that many editors and browsers don't display
unicode art properly, so I'm also including a screenshot of the same
document.

                        ┌──────────┬───── Internet
                        │ │
                        │ └[understudies]
                    ┌───┴───┐
                    │ Alpha ├──┬─────┬──┬───── DMZ
                    └┬──┬──┬┘ │ │ │
                     │ │ │ │ │ └[zhug &c]
    test ─┬──────────┘ │ │ ┌┴─────│──┐
          └[potential │ │ │Omega │ │ ← storage
            looneys] │ │ │ ■ ■ ■ │ ← VMs
                        │ │ └────│───┬┘
                        │ │ │ │
    unmanaged ─┬───╥────┘ └──┬─┬──┴───┴── managed
               │ ║ │ │
    [unmanaged │ ║ │ └[managed clients]
       clients]┘ ║ ← VPN │
                   ║ └─[internal, non-
    wireless ──────╨──┐ critical servers]
                      ┊ ← 802.11
    [wireless clients]┘

[Trent W. Buck (twb)]

And since Launchpad doesn't seem to handle Unicode art inside ticket
comments very well, here's the original network.txt as an attachment.